This CML program project grant represents an integrated program consisting of 7 Departments, 2 Divisions and 1 independent program within M.D. Anderson Cancer Center. The interaction of the clinical and laboratory programs is designed to foster the establishment of new therapeutic directions for CML and the development of laboratory assays which will be of help in identifying determinants of therapy sensitivity and in measuring response. These biological studies will provide the basis for new directions in therapy. In order to accomplish this program goal, a core in which the programmed collection, fractionation, distribution and storage of samples, in close affiliation with the clinical and laboratory programs can take place. This therapeutic research program involves the analysis of the molecular and biological changes which occur during the evolution of response or resistance to chemotherapeutic agents, combined biological and chemotherapy and bone marrow transplantation. Serum peripheral blood cells are to be collected at predetermined intervals throughout several sequential therapeutic interventions, outlined in Figures 1 and 2 and Table I. These samples must be distributed to the appropriate project collaborator in all Projects 1-6. Engrafting doses of peripheral blood mononuclear cells or bone marrow cells manipulated by in vitro growth must be collected, processed, stored and re-infused into patients undergoing autologous or allogeneic bone marrow transplantation. This core is designed to provide for the collection, processing and analysis of these samples.